Signal recording and reproducing



Sept. 14, 1943.

c; w. THIEDE 2,329,492-

SIGNAL RECORDING AND REPRODUCING Filed Aug. 22. 1940 5 Sheets-Sheet 1 mvsmon ferd/nhnd C. 14. 777/190? ATTORNEYS p 9 19431 F. c. w. THIEDE 2,329,492

SIGNAL RECORDING AND REPRODUCING Filed Aug. 22, 1940 5 Sheets-Sheet 2 ATTQRNEYS p 1943- F. c. w. THlE-DE 2,329,492

SIGNAL RECORDING AND REPRODUCING IINVENTORI. ferdI/IafldQM/M/Me ATTORNE Y5 p 1943- F. c. w. THIEDE -2.329,492

SIGNAL RECORDING AND REPRODUCING FiledAug. 22, 1940 5 Sheets-Sheet 4 INVENTOR. Ferd/mm C W Tlr/ede A T TORNEYS Sept. 14, 1943. F. c. w. THIEDE ,3

' SIGNAL nncomame 'Ama nmrnonucme Filed Aug. 22, 19 10 5 Sheets-Sheet 5 AMC. Dev/Ce Defeczor INVENTOR. Era/77404 a W Th/ede AT TORNEYS 1 fl efecfar the switching device also-causing the connection 7 tion of a switch, such a s tha't 'justdescribed, to

Patented Sept. 14, 1943 *SIGNALRECORDING mzmonoomoj Ferdinand C. -W.' w-Thiede, Hernpstead, N.;y.,;as-

signor :to :B. A. Prodtonflompany, lna, New York,iN. 1., a corporationof NewYork V i v a plication August 22, leroj seriar m 353,612

This invention relates to' a signal'recordingand reproducing "device; and more especially to a device of the type 'in'whicha record ofthe signal is inscribed in the form of a sound track'on a movable record. Such "a device is described in application Serial No; '218,' 082,'fi1ed lu1y'8,"1938, in the name of Barton Proctor and Ferdinand C. W. Thiede, -I-n said application'an audio ire-- quency amplifying "device is "disclosed and in "association with which a switching device is provided, whereby areproduc'ing device may be 'connected with'the input circuitofthe amplifier and "its output circuit-connected with a loudspeaker in which the recorded signal is reproduced. 'In another position of the switching "device, the'output circuit of'the amplifier m'ay fbe connected with a recordi'n'gunit,'which records a sound track corresponding to the signal on a "movablerecord,

of a microphone to' the' "input circuit of the amplifier, into which' niicrophone the operator dic- 'tates the communication to be recorded. In the aforesaid application, the feed of the record is initiated by the lowering of a feed rollerin'to a manually controlled lever forming part ofthe recording device. 1 r i V I, A recording and *reproducing devic'e'o'f a similar type is disclosedin'patent {application 'SriNo. 281-,8 1 1, filed Ju e 29; 19379, the name tears ton A. Proctor, but in which the lowering of the .feed :roller into engagement "the record may be controlled *fro'rn a-remote point', at which a manually operated -switchf is *provided. ,"This switch is connected through {a circuit which iterrninates in a solenoid disposed near the record, and the actuation of which -'operates a ratchet device which in'turn -rotates a oam, whichype'rr'nits theieed roller to be urged against the surface of the record {under the bias 'o'f' a spring. The rotation o'f the record then continues until" the switch is again actuated -to'co'mpletethe oil"- cuit leading to the solenoid whereupon a further rotation of the ratchet device causesfa highpoint on the cam to engage the lever carrying the feed roller and move the feed, roller oi? the record,

which immediately 's'tops'. I

" A 'rnain' purpose of' the present invention is the pTOV1Si0I1.Of means whereby the manual opera-i vllO The recorded "consists of speech, the starting 1 and stopping of the recording device. is automatically control led byfthe voice of/thef operator or dictator. v According'toa further object of the invention,

'Where'thes'ignaltobe recorded 'c onsists of alradio transmission; the starting and stoppingfl'of the recording device is automatically controlled in re-' *sponseftjo the reception of the carrier Wave by- -m;eans 'o'f' 'a -radi0receiver preferably disposed "near the recording"device. j

In further "pursuance of this object, the arrangement is preferably such that the. rotation of the recordon which the recordingis'to. be

inade is initiated as soon as the carrierfltwave is received while tl ie recording stylus itself is "actuated by r neanjs of electrical currents "correspending :to'fthe signal modulation frequency v which are detected and arnplified in the receiver.

engagement with the-record surface by means of {35 These signal modulations may be of any pre ferred 'typeiand inay consist for example of speech, mu-

'sic,- code signals-orany otherknovvn type of sig- -nal impulses. h fur'therobject of thefinvention is the provision of "means for, supplying energizing currents to the recording device which provides; for the I continuedfeeding of 'the'record during short intervals normal-1y existing between successive pormatically in response to the tone modulations fdf 'ti'o'ns-o'f the signal; such as short pauses between wordsorfsen'tenc esv therein, but which automatically interrupts the feeding of the record at the end ofthe communication or signal or if the signal is 'purpos elyinterrupted, r'esulting in ,a long interruptiontherein. The means which controls the {feeding iot thelreoordin g device preferably comprises :afslow acting or delay relay, which serves toiinsurethe Contact of the drive roller with th'ero'tating record during the short interruptions nor rnally present between successive portions of the signal, -but which permits the drive roller to be disengagedifrom therecord in order ito-fstop its rotation at the termination ofthesigfnal'. Accordingto one embodiment of the invention, tlii'sfdhyrelay is energized by the same audio frequency amplifier which supplies the currents [to operate the recordingstylus,

anlr alternative me fo actuating such a delay relay, it is. a further object of the in-vention 'to provide a sound pressure relay which-is preferably disposed adjacent to the recording microphone and which. closes the :energizihg-eircurt 10f theldelay relayfin response to the sound waves generated by the operators ,voice sound pressur'ei relay i's preferab1y'of..thetype I which c'lqses the relay :circuit by means of a pair 7 'I HEJI-"to :be recorded. *Wherethe-signalto 5'5 of'cQoperatiI'I'g contacts, one of which is actut a further object of the invention to provide means whereby the signal may be continuously recorded, without any interruptions "between its several parts, on a second record. 'In' so doing, the second record is automatically started at the commencement of each separate portion of the recorded signal and automatically stopped.

at the end thereof, whereby a continuous record of the signal is secured without any'in'terruptions therein on the second record; 'This,ar'-' rangement also provides means whereby the recordings on a plurality of small records may be readily transferred as a continuous recording onto a single large record.

Other and further objects-of the inventio will become apparent to those skilled inthe art as the description thereof proceeds. For a better understanding of the invention, reference is made to the accompanying drawings wherein similarparts are indicated by the same reference numerals andin which:

Fig. 1 is a diagrammatic representation of certain parts of a recording and reproducing device embodying the invention, includinga circuit diagram of its electrical connections; 7

Fig. 2 is a diagrammatic representation of a device similar to that shown in'Fig. 1 with certain modifications in the circuit connections 7 thereof Fig. 3 is a diagrammatic representation of a device similar to that shown in Fig. 2 arranged for transferring previously recorded signals onto arecord; v

Fig. 4 is a plan view of a record adapted for use with the recording device shown in Fig. 3;

Fig. 5 is a diagrammatic representation of certain parts of a recording and reproducing device and its circuit connections embodying a modified form of the invention; and

Fig. 6 is a diagrammatic representation of.

to the pawl lever 22. fnoidcoil 24 causes the lowering of its plunger 25 resulting in a single step of rotation to the l4 pivoted at 15, and having a tail piece l6 biased upwardly by means of a spring IT. The mechanical means for moving the feed roller I3 into and out of engagement with the record 5 is similar to that disclosed in application No. 281,811 and comprises a shaft 18 carrying a ratchet wheel i9, and a pair of cams 20 and 2|, each of which has three high points and three low points. as shown; For rotating the ratchet l0 l8 and carries a pawl 23 adapted to actuate the ratchet. For rotating the pawl lever 22, a solenoid having a winding 24 is provided, the plunger wheel is a'pawl lever'22 is pivoted on the shaft 25 of which is connected by means of a link 26 Energization of the soleshaft-l 8 and the cams 20, 2| through the pawl :ward one tooth 23 and its ratchet wheel [9. As soon as the flow of current through the coil 24 is interrupted,

a spring 21. returns the link 26 to its upper limit invention have to do with the means for controlling the energizing current of the solenoid 24. The circuit connecting the coil 24 across recording and reproducing device illustratinga further modification of the invention adapted for recording radio signals and including a circuit diagram showing portions of a connected radio receiver. 1 1

The present invention relates to a recording and reproducing device of the typedisclosed and claimed in the above referred to application, Serial No. 281,811. Referring to Fig.1,"the device is shown as comprising a reproducing unit I having astylus 2, a recording unit 3 havinga "stylus 4, shown in engagement with a thin flexible record 5. The lower surface of the record 5 is shown in engagement with a lower feed roller 6, secured to a shaft 1, carrying a large pully 8, Which is driven by means of a belt 9 from a motor pulley ll] of an electrical motor ll, supplied with current from the power. lines L, upon the closure of a switch l2. For simplicity the record 5 has been illustrated as plane, 'but it will be understood that it is preferably curved over a turtleback support, as shown .in the aforementioned applications.

- 'Mounted above the record and opposite the feed roller 6 is an upper feed mne'r l3 which is rotated in the opposite direction to feed roller 6 by the pulley 8 through means not herein shown, when brought into engagement with the record. The roller I3'is mounted on an arm the supply lines Lisshown as comprising a lead 28 and a lead 29 terminating ina movable switch blade 30 1 disposed between thecontacts 3 I, 32 which areconnectedto a-sim'ilar pair of contacts 133, 34bythe upper and lower-conductors 35, 36.

The. other side of .the lines L is connected to the armature 31 of a delay or slow acting relay 38,

the end of the armature 3'l being disposed-between the contacts33, 34 as shown, The circuit of relay 38 includes a battery 39 and is adapted tolbe closed upon the energization of a quick acting or audio relay 40,'having an armature 4|.

In the embodiment of the invention shown in Fig. l, the winding of relay-4ll is energized by currents corresponding to the signal modulations .to be recorded by means of the circuit shown, in-

cluding the secondarywinding 42 which is cou' ,pled to the first stage of an audio frequency am plifier of the type disclosed in the; aforesaid applicationfier. No. 218,082. This amplifier com- ;prises the amplifying tubes 43,- 44 and 45 which .are ponnected together by the circuitshown and which are supplied with energizing currentv by means of a rectifier 46 and filter device 41. .Also,-as disclosed in-said-application, a man- ,ually operable switch control shaft 48'is pro- .vided, for-the operations of recording or reproducing,. this ,shaft; being provided with the switches 49, 50, 5| and 52. A jack 53.is connected to the switch arms; 5|, 52 so that either a microphonespeaker 54 or a telephone search coil 55 may be plugged in and selectively con- :nected to the primary winding 56 of the amplifierinput transformer 51. r

M For recording a communication spoken before the microphone 54, its circuit is plugged into the -jack-53 and the power switch l2 closed to start the motor H, which causes the rotation of the lower feed roll 6. The recording unit 3 is then lowered into the position shown, with its stylus .4 in engagement with the record ad- .jacent:.to its drive spindle bymeans of the manual controldevice (not shown) described .in;said, appl ication Ser. No. 281,811. The voice currents generated by the microphone 54 in primary-winding 56 are amplified in the tubes 43, 44.and; 45, the amplified currents appearing in and switch arm'l9,similar tothat s own'rhrigure 2, and also includes a jackl8 which' mayfb e plugg'edinto the circuit. The record a'may'be of the type shown in Figure 4, on which acornmunication interrupted' at intervals has been're corded, or on which a plurality of difierent communications have been recorded at, spaced "intervals. Those portions of the record representing communication are indicated by thef refer ence characters C, C and C", the spiralrecord ing stylus 4 records thecommunication previously recorded' on'the first small record; Upon the reproducing stylus 2a reaching the'fendof the recordingon the first record 5c, the feed roller I3 is' automatically raised from the record 5 in'the manner heretofore described, and rotation or the record5 immediately ceases. The next small'rec- I ordis then insertedin jthe reproducing machine groove between thej'inscribed record portions being designated by the reference characters fs and S. Instead of the coil 42 whichsupplies the energizing currents to"the 'winding of relay 4!} being connected to the outputcircuit of tube 43', as shown in Fig. 1, a correspondingcoil is shown at 4 211 as being coupled to the output circuit of amplifier 44. M For recording theseveral spaced apart or interrupted communications on the record5a as a single continuous'recording onthe record 5, the jack 6B is plugg'e'din and the shaft 65jadjusted into the position sh0wn ,'to' lower ,the reproducing stylus 2a into contact with thesurface of the record 5a at the'inner end of the spiralgroove' thereon. As the feed of the record proceeds, upon the vibration of the stylus 211 at the commencement of the inscribed portion 0, the amplified signal currents-appearing in the coil 42:; cause the operation of audio'relay' 40, the operationpf into engagement with the record'5 withth con:

-relay 38, and the lowering of the feedro ller ld sequent recording of the communication C in the manner above described in connection with the operation of Figure 1. The recording continues until the end of record portion C passes under the stylus 2a, whereupon'no energizing voltage'is developed in the coil 42: to operate-the relay 4!), whose release results after a'short interval in the release ofthe delay relay 38 and the elevation of feed roller. I3 from the record 5; which immediately, stops, as. above describedin 'corinection with Fig; 1. the reproducing stylus 2a is passing over the spiral groove in the portion Sbetween the record portions C and C". A's-soon as the beginning of the recording C, passes under recordingstyl'us' 2a, the amplified signal currents developed' in coil 4220, again energize-relay, delayrelay"38 and cause the, feed roller .I3to be'again lowered into engagement with the record 5'and the re cording stylus 4 to record thereon the communi-- cation represented .by C on the record 5a. Thisprocess continues until all theicommunic'ations represented .on the record 5111: have been"trans-.'- ierred as a continuous record ontothe record 5. Instead of the communication portions C, C and C being disposed on a-single recordythey may be disposed on separate small records which may beplaced' on the record spindle A one after another in thepos'ition shown by the record 5a.

In this case, as soon as thereproducing stylus 2c. is actuated at'thei'ri'ner end of', the"recording on; the first record, the feed roller 13, isauto'matically lowered into engagement with the'surfa'ce of 'the large record 5 whichimrnediately commencesfto rotate. This 'rotati'on'continues' and'the 'record-" This record remainsfiat rest "while" with the: record to ,the winding 56 and theprocess repeated untiljthecontents of all the small records has been recorded on the single large record '5 as a continuous communication.

The embodiment "Of the invention shown in Fig. i' is similar to that shown in Fig. 2 except that instead 'of deriving the actuating currents for the delay relay 38 from the amplifier circuit through the circuit connection including condenser '64 (Fig; 2), they are derived from a sound pressure 'relay 69 having a 'diaphr'agm'lfl which carries 'a movable contact H adapted to engage a fixed contact "connected with the local battery" 39; "Thesound pressure relay 69 is prefere ably disposed adjacent to the microphone 54 so that as soon as the o'peratorcom'mences to dictate' beforev the microphone, the sound pressure generated by his voice causes the diaphragm 10 to vibrate and' close the circuit of 'thedelay relay 38. j The closure of this" circuit causes the auto matic' lowering of tljle feed roller l3and therotation of the record'5 in the manner, above described; As t e dictation continues, the relay at 1's energized at'rreq'uent intervals by theolos'ure'of contacts He-'72 so that the relay armaa tore 31 is sustained and rotation or the record 5 continued, the communication being continuously recorded there'on by the recording stylus 4. fit the termination of the dictation, the diaphragm' 10 remains :at rest with the contacts l'l*12 separated, causing the release of relay armature 31 'afterja short interval and the eleva tio'n of feed roller |3fand consequent stoppage ofqthe record 5 in the manner above described i'n-conriection with Fig. 1. In this embodiment also, it'will be understood that if for any reason the dictator makes a long pause as, for'example, several seconds, in the' dictation, the delay relay 38 operates to'release its armature '31 and the record 5 iszautomatically stopped. Upon resuming the dictation,- the relay38 is again'energized, the feed roller l3. again'lowered into engagement 5 and its rotation continued as before; I 1 l The embodiment of theinventionishown in Fig. Gisgenerally similar to that shown in Fig. 2 but instead of .the energizing currents being supplied of thetransformer 57 by the microphone 54, they are supplied by the detector r stage 13 of a radio. receiver R herein illustrated or more intermediate as of, the superheterodynetype and comprising afirs'tdetector l4, 'a.,loca1 oscillator r-'15,.and one I I frequency amplifier stages The receiver also preferably comprises an automatic volur'necontrol device 1 .which-iscoupledfto theoutput of the amplifier stage 16 and controls its, grid bias and hence its transconductance, inversely asthe strength of 'the carrier g n the receiver R to the amplifier stage 43' comprises the'primary'coil 56'and aswitch arm 18 secured we We seeme;., ied fl e fi i eqw ir d-c rrier,frequcn yethe plate. urrent oi amota ina-ihe 99 v 'eompr sinea e naasta na e mem r a ed-.1 en a e h elq n f Q aQfi-a rt e: cord, 1ecord'ng means adapted; to record the s ignaldon ne e an enn de i e. fk x In this embodiment oft and pin ip there] rdfl i'ieae re li d.b

s n e re x il.,.wh ee i ie nn qbe heelie:-ei tavinsith ccqrd w r en in ri s e we n the Q 6,-. and. s urce of pos Qi i li rpi ampl fier, h irep a means means r on tqy e s -eil m99 h s: oiihe iena im aut matic l y am on a sf:

' E small mass and inertia cornprisinge-in coinbinae" 5 he record; m an compr n at .le on d-r The armature 31a of relay 80 operates bet en moving said feed Wheel into direct engagement r 1h .Ltii -th lsii ia eoi t e reco d. imm atethe. re

- f In-insing the device; to record E a br adcas L V ot.-s s a ,:.the Jac is pl g ed into con t}. r e icr ph ne-sneakerii to theeo ut .9 afd vi 5 s rd ie;af ieiiai h v mp fie st e 45v anditheswi ch ha t 1 a d:- oye modulations n ammfiexip e disc record iustediintoe he nositionishq ne. withe hepqwr flemall 2335 @Pdinerfia qm s nai combie ndmeans comprising an; electron discharge v .7 e v I a ir n de ice i nnener i narthesi nal-o p o am compri ng sneechrmu is; Mother-m 2, re or s by th am l fi dvsienal-modce;t

w tch l2 c osedand theerecordineun ..l wi-r.natib igar qrfl un tha ns asiyl s arranged;

redjintc rthe'position s icmszrl.with it tyles in en ement. with. the: .IBQQI'QLJ'JQKQJ .rit r ter, and with the receiver untuned to the,

a r I friction roller p r-mtubeiflerpassing.lthronghethe,windinsd ii aptedtqepgag the iac i; e re rditse1r;.. r ay 7870: is, sufficienteto .causeits; armature 3Iam ne, i'or' normally to be retained in contact, with thegrcontact 34g, 5" f on 119 er outci engagement; with the face as shownuUponfltuningr the inputicircuitdl; of,, 'of th e record; inafis responsive to the tone. the receiver to the desired carrier-.freque e by m filatigns o the signal for moving-sa1id;fric any suitabietypc of-iuning; means: as-,,,=f9.r .ex- 19 6 r v, amp1e,-;the variable; condenserfll, the. actionzzof s, 4 the re or to rotatev-the record under the-stylus,

' theautomatic yolumecontrol-devicee111 causes, ean jesponsive to afcessati n o rfi el ignal the negative bias:vo1tage-on -theugriddofstuber16, rrio'dill-ationsf for-"automatically; rendering. said v to. increaseuandethus:decreasetherplatecurrent; Y 7 I131 ans} effective to; moye jheqfr iction of,,the,@t11be..s.,.,'I1'1i S; reducedeqcurrent; passingr m-.,. ne 75 99-0? the-vrecordyandr throughgthe winding of re1ay-.i80;ecausesuitsrare; 1121313? recording-means bythe mature 31a to move-into engagement-mithicone i 'fm iilatie 's aintainingvsaid tact 3311b .In; the mannenebove ex lained in. ZISLIAdev or"reqq d ii e a is i avin -1 tone connection; with Fig.- .1, "this. causes :thernieed, ""dul a-thin-disc}recordofsmall mass. roller 13 to be.movedinto.engagemeninwithgthe, inert a 003 11; sing in; c mbina ion, t surface-orthe.recordedr nditherecormrotate; rnea h ne d'tqeng e the w r fa e under therecordingsstylus The-,incoming-h-sig-p. 40 o' ff'th ecordtoisj pportit, meanscomprisingea, nal modulations ,are detectedzin'nther. detector Pa robp eq q:.W i e fi d: to directly 13 andiaften being. amplified'zlinntheamplifier. lig pp e befi 9 the; record' it'selfx stages e43-,-;4.4..and.-:145;areapplied tohthe recording; 'I'wdtafifig'th" cord,- control means responunitr3' throughythe circuit shonm ,vvincluding:-the N Siye tolthe s gnal inodnl ations;,i9r;automatica;11y secondary winding 58- andeswitchaiarmeiili l he; refider i g ll f qfl fie fi.,ifi Qbi e toirotate. signal modulations thus; being recordedronzthee corfigl eaw prapil yingthe signal mod recordsibythe recordingistylusrk. .mhiszrecord- 011's to v s'aid control rneansn ad'controi ingzcontinues asslongrasithecarrienfnequency is; means including a delay' dev-iceyfor causing the received oruntilithe=mputcircuitziiileis: detunedaa: saidflfeed h ls tohcqt rt n musly eng e a d In either of ,these'fevents, the action oi theauto-ri m r re e-record during-brief intervals between toincrease; The increasedcurnentthroughthei. ig d la ti .y s .e Windme 0 r y- 0- t 4 eezflnejucombination a 4 setrdrtn m c1aini 3 in Pulled mtmengagement m 5a which theidelay de'vice is adapted to render-the said ;f'ee"d -wheels mene'etii e te rdt-a te the record mediately comerto resteinethermannereabovee-dee-e 13 1wi ?%f*m? apph'; scribed in connectiomwithflig. v1; ..-1Z uringl. the ii mfi -m 9 recording process,thegsignals,,v-beingeirecorded m I Q. x are reproduced in the speaker. soethatrihd x fiim fif'iw iqmg $8??? p jY Pg P f; operator is at allrtimesi aware whether a m didri W egers??? y rr s a PQ latedzsignal is beingqreceivedw ,From:.the above; 1 ny e q q 'EPQ WFPPZQ YFQJWWW description',rit,is.apparentthat;theystarting and m I fQfa flif gf a ii d io stopping of; the.;,recordingpmechanism is auto- '5 r9 the r cori i; an lectron dlscharefe A matically controlled-11bit; thearadio signal to be; mpllfi 'f v havmg i and i ilq t q recorded. 1. 1 I jcuits, means for appiyingthe signal modulations I havedescribed 'what -I believe-fiche the bee ii i fi p l irc'ui rm n j p ner; emioodimentseof mY;;invention,.- [Ldo not-,wish-- g'i 'i W H iileahs arnphfi ed' however, .to.,-ahe; confinedlzto theeemhodin ent 0 s1 IIIQ-Qliihtl s japriearmg n the ontpnt; Cirshown, clout" Whatledesirey.-tocoverJ23 Li??? 9 1 ii u g r; i va qe m u l d 9; Patient is; set forth in the; appended claim th e piitpnticircmt ofthefiamphfier and-contror ;.I'c1aim:,; I

1: A device iiokr if rgignarl ari one biasiof tube- 16 to: decrease-audits plateicurrente; encr Z ng; the fiignal; recording? means? with tiif aid relay deVice -for' 'catisin prriprisii'i'gf atrota'table step by s-ted de I said rotatable means in response fied signal modulations. 4 1 r I 6. A combination as set forthin claim 5 in which the control means comprises a delay relay arranged to cause the continuous rotation of the record during brief intervals between successive portions of the signal, a circuit including a switch for energizing said delay relay and means energized by the amplified signal modulations for closing said switch. Y

7. Adevice for recording dictation on a thin disc record of small mass and inertia comprising, in combinatiomstationary means for supporting the record, means for rotating the record including a friction roller mounted for movement towards and away from the record, meansfor maintaining the-friction roller normally out of' engagement with the surface of the record and means responsive to the operators voice -ar-" ranged to automatically movethe friction roller into direct frictional engagement with the surface ofthe record to rotate it.

8. A device for recording dictation on a record comprising, in combination; a feed wheel for frictionally driving the record, control means operable step by step to engage-the feed wheel to the ampli- I with the record and to disengage the feed wheel from the record at alternate steps, and means controlled by the operators-voice for actuating the control means step by step.

l 9. A device for recording a signal having tone modulations on a record comprising, in'combination, recording means adapted to record the siga for supporting it, means for energizing the signal nal on the record, rotatable means adapted to' rotate the record,-an electron discharge tube amplifier device having input and output circuits, means including a microphone for applying the signal modulations to the amplifier input circuit, means for energizing the recording means with the amplified signal modulations appearing in the output circuit of the amplifier and control" means includinga sound pressure relay for causi ing the rotation of the recor under the action of said rotatable means. 9

10. A combination-as set forth in claim 9 in" which the control means includes a delay relay connected to the sound-pressure relay and in which the sound pressure relay is disposed ad'- Jacent to the microphon 11. A devicefor recording as a continuous S1gna, 1,.O11 a thin discrecord of small mass-and inertia av series of signals previously recorded discontinuously on a secondrecord, the device comprising, in combination, recording means adapted to record the signallon the thin disc record, means forrotating the first record with reference to the recording means, a stationary member engaging the lower face of the thin disc record for supporting it, means for continuously advancing the second record, means for energizing the signal recording means in accordance with the signals recorded on the second record andmeans responsive successively to each of the recordedsignals on the second record to automatically render the record advancing means efiective to alternatelyrotate and stop the thin disc record; I

12. A device for recording as a continuous signal on a thin disc record of small mass and inertia a series of recordeddiscontinuous signals, the device comprising, in combination, record-f ing means adapted to record the signal on the record, means for rotating ,therecord withref--v erence to the recording means; a stationary. member engaging the lower faceof the record for energizing said recording unit by the" am- ,means in circuit of the amplifier tube.

recording means in accordance with the recorded signals and means responsive successively to each of the recorded signalsior automaticallyrendering the record rotating means efie'ctive to alternately rotate andstop the record. r

'13. The device as-"set forth in' claim 12 ii whichthe recorded signals comprise a plurality of sound; tracks formed on separate thin fieiiible records. 11 v a v.

' 14. A devicefor recording signal nodulatioris transmitted by radio frequency carrier currents on a record,'the device comprising in 'combination, recording means adapted to record the signal modulations on therecord, means adaptedtoadvance the record with reierence to the reco'rding means, means responsivefto' the cariierjcur- 1 rents for automatically rendering'ithe record; ad-

vancing means effective; to advance the record and means for energizingthesignal reco'rding tions.

15; A combination. as set forth iii-claim 14 in which the means responsive to the carriercurthe carrier waves. H l v 16. 'A device for recording signal modulations transmitted by radio frequencycarrier currents on a'reco-rd, the device comprisingfln combination, recording means "adapted to record-the signal modulations on the record, means adapted to advance the record along'the pathof'the recording means, a radio receiver having input, and

output circuits, means connecting said recording means, to the receiver-output circuit and control means whereby the, tuning of the receiver input circuit 'to the t carrier frequency automatically renders the record advancing means effective toadvance the record.

17.'A combination as set forth in claim 16 in whichthe radio receiver is of the superheterodyne type and comprises an intermediate frequency amplifier tube and in which the control means comprises a'relayiconnected to the plate 18. A device for recordingsignal modulations transmitted by radio frequency 'carriercurrents on a disc record, the device comprising, in Come. bination,i a recording} .unit having ;a. stylus adapted toengage the record and record the signal modulations thereon, means arranged to rotate the record under-the stylus, means responsive' to avreceived carrier curr'entfor autoamplifying the signal modulationsland means plified signal modulations. l l 19. A device for recording the signal modulations of a'carrier wave ona record comprising, in combination, "means for advancing therecord, a radioreceiver' tunable to the carrier.

wave and having an electron discharge tube am-.

plifier, and an" automatic volume control device arranged to regulate the potential of the grid of said discharge tube inversely in accordance with the strength of 'a received carrier 'wave, means energized by the'amplified signal modulat ions for recording the signal modulations von the record and means responsive to the adjustment of the potential or the grid or said dis-- charge tube by said automatic volume control device to a predetermined-value for initiating accordance with: the signal modulathe advancement of the record by said record advancing means. i

20. A device for recording dictation on a thin flexible record of small mass and inertia comprising, in combination, a stationary member arranged to engage the lower face of the record for supporting it, rotatable driving means comprising a friction roller for rotating the record,

control means operable step by step to engage the friction roller with a face of the record and to disengage the friction roller from said face at alternate steps, and means controlled by the operators voice for actuating the said control means step by step.

FERDlNANl) c. w. THIEDE. 

